Japan's Hayabusa Missions: Pioneering the Collection of Asteroid Samples

Japan's Aerospace Exploration Agency (JAXA) has been at the forefront of space exploration and study, with its Hayabusa missions leading the charge in asteroid sampling. These endeavors have not only furthered our understanding of asteroids but have also given us invaluable data about the formation and evolution of our solar system.

Hayabusa: The First Foray into Asteroid Sampling

Launched in May 2003, Hayabusa, meaning 'Peregrine Falcon' in Japanese, embarked on a mission to rendezvous with and collect samples from the asteroid Itokawa. The spacecraft encountered Itokawa in November 2005, where it attempted multiple touch and go maneuvers for sample collection.

Hayabusa2, JAXA's asteroid explorer, and the MASCOT lander, developed by the German Aerospace Center and the French space agency. (Image Credit: DLR)

Despite a series of challenges, including a crash landing on the asteroid and lost communication with Earth, the spacecraft managed to return safely to Earth on June 13, 2010. The journey was not without its rewards. Although the sampling mechanism did not function as expected, the spacecraft managed to bring back particles from the asteroid, marking the first successful retrieval of direct samples from an asteroid.

A Closer Look at the Itokawa Samples

The samples returned from Itokawa were significantly smaller than anticipated, but their scientific value was immeasurable. The particles collected were found to be asteroid grains based on their chemistry and mineralogy. These grains were mixed with contaminant particles from the spacecraft, providing valuable context to the asteroid's geological profile.

The Hayabusa Joint Science Team, made up of scientists from Japan, Australia, and the United States, performed the initial analysis of the samples. Their findings have been invaluable in understanding the composition and nature of asteroids, contributing to the broader knowledge of our solar system.

Hayabusa2: A Second Journey into the Unknown

Continuing the legacy of its predecessor, Hayabusa2 launched in 2014, aiming to retrieve samples from the asteroid Ryugu. Unlike the first mission, Hayabusa2 aimed to collect material from both the surface and interior of the asteroid. The mission was a resounding success, making it the first-ever collection of subsurface materials from a solar system body other than the moon.

A canister containing a sample of asteroid Ryugu is transferred from JAXA to NASA. (Image Credit: NASA/Robert Markowitz)

Hayabusa2 conducted remote observations, released several rovers onto the asteroid, and even managed to collect surface samples. It also created a crater on the asteroid's surface, exposing fresh material for sampling. After it collected the samples, Hayabusa2 embarked on its journey back to Earth.

The Return of Hayabusa2 and Analysis of Ryugu Samples

After completing its mission, Hayabusa2 returned to Earth in December 2020, bringing back 0.2 ounces of precious asteroid cargo. The returned sample was considerably larger than that of the previous Hayabusa mission, providing a wealth of material for scientific study.

The initial analysis of the Ryugu samples revealed the asteroid's rich carbon and water content. Interestingly, the samples were slightly different from other carbonaceous chondrites previously studied on Earth, suggesting that Ryugu may contain a previously unstudied component of carbonaceous material.

The Challenges and Triumphs of Sample Transfer

The process of transferring the Ryugu samples from Japan to NASA's Astromaterials Research and Exploration Science (ARES) center in Texas was not without its challenges. Due to the COVID-19 pandemic, the planned in-person selection and transfer of the samples had to be conducted digitally. Despite these hurdles, the precious cargo was safely delivered to Texas for further study.

Comparing The Itokawa and Ryugu Samples

The samples from Itokawa and Ryugu, despite coming from different asteroids, provide a unique opportunity for comparison. By studying the samples collected from the surface and interior of these asteroids, scientists can gain insights into the origins and evolution of the solar system.

An H2-A rocket carrying space explorer Hayabusa2, lifts off from a launching pad at Tanegashima Space Center in Kagoshima, Japan, Dec. 3, 2014. (Image Credit: Kyodo News/AP Photo)

The Significance of the Hayabusa Missions

The Hayabusa missions have made Japan the only nation to have acquired samples from both the surface and interior of an asteroid. The samples returned from these missions hold significant scientific value, potentially providing clues about how our solar system was formed and how water was brought to Earth.

Future Endeavors: More Asteroid Sampling Missions

The success of the Hayabusa missions has paved the way for more asteroid sampling missions. NASA's ongoing Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer mission also plans to bring samples from an asteroid, named Bennu, back to Earth in 2023.

The Hayabusa missions have shown that space exploration and asteroid sampling are not only possible but can also yield valuable scientific data. The samples returned from these missions offer a unique opportunity to study the origins of our solar system and potentially answer some of the most pressing questions about the universe. As we continue to explore the cosmos, missions like Hayabusa give us the tools to unlock the secrets of our past and shape our understanding of the future.